Conventional individual section or IS glassware forming machines comprise one or more sections, each of which is supplied with one more more gobs of molten glass. These gobs are formed into containers or other glassware in each section of the forming machine by transfer mechanisms and molds which are primarily pneumatically operated. Each part of the manipulative mechanism of a section carries out a separate step in the formation of finished ware and is controlled by operation of a pneumatic valve. Initially, the various operating valves were controlled with respect to each other by adjustable cams carried on a rotatable timing drum common to all cams and valves. See U.S. Pat. No. 1,911,119. More recently, it has become desirable to implement electronic control of the operating valves of each machine section. U.S. Pat. Nos. 3,918,489 and 4,100,937 disclose valve block assemblies which include a plurality of air-operated poppet or cartridge valves for controlling operation of associated mechanisms of an IS machine section, and a corresponding plurality of electrically-operated solenoid pilot valves for controlling operation of associated poppet valves. The solenoid and poppet valves for each section of an IS machine are mounted in a common valve block assembly and share manifold and exhaust lines. An electrical connector on the valve block assembly enables connection to an external electronic control device, such as a programmable controller or control computer. The valve block assembly may be readily removed from a forming machine section for repair and replacement by another like assembly, and thereby minimize downtime of the forming machine.
When placing a valve block assembly in operation in an IS machine, it is desirable to possess accurate information concerning operating characteristics of the various valve mechanisms in the valve block assembly with respect to each other so that motion at the IS machine may be closely controlled. Wear at the seals, spools and springs of the various valves increase operating delays. However, variations in operating characteristics may be accommodated within a fairly wide range by corresponding variations in the control programming, as long as such operating characteristic variations can be readily determined. It is therefore important to test operation of the various valves in situ on the valve block as it is to be employed in the IS machine so that wear and tolerance variations can be determined and accommodated.